A dead man’s switch, explained
A regular action whose absence starts an agreed response. How the dead man’s switch principle works in check-in apps, and the limits to understand.
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An emergency button requires an action when help is needed. A dead man’s switch reverses that logic: it requires a regular action during normal life. When the action is missing, the system starts an agreed response.
The name can sound harsh for an everyday habit. In a check-in app the action is simply a confirmation: I’m here. The system does not need to watch your day or know why the confirmation is missing.
An absence becomes a signal
Imagine an agreement between two people: one gets in touch regularly; if they do not, the other tries to reach them. An app can remind the person to confirm and notify the contact once the agreed period has passed.
That means no button has to be pressed during the event that prevents communication. The trade-off is time. The absence is only recognisable once the interval expires. Where an immediate response is needed, applying this principle to a daily check-in is not enough.
Three settings to understand
The interval. It needs to fit real life. Too short can produce many forgotten confirmations; too long can delay the point at which someone asks for news. No single duration suits every situation.
The reminder. Before involving somebody else, the person should have an opportunity to confirm. Ondira sends push and email reminders. A grace period, normally two hours but adjustable, comes before the contact notification. Quiet hours matter too. Our how it works page explains the full sequence.
The response. A message only helps if it reaches someone who knows what to do. The contact should have agreed to the role, read the inbox and know how to call or reach the person. Technical setup cannot replace that agreement.
The system does not know the cause
A flat battery, no signal or a forgotten tap can produce the same absence as a real inability to communicate. The notification says that the check-in is missing, rather than reporting a detected accident.
The other direction matters too: a check-in confirms an action, not a medical condition. For someone living alone, it can be a useful arrangement without becoming a health assessment.
Similar principles can serve different needs
A professional system for lone working may need sensors, a rescue chain and very different response times. Two tools sharing a principle are not necessarily equivalent.
Ondira detects no falls, measures no medical information and calls no monitoring centre. The free version offers intervals of one to seven days; Plus adds eight- or twelve-hour intervals and a weekly schedule. Check the deadline and agree the contacts. For an immediate emergency in Switzerland, call 144 or 112.
Frequently asked questions
Does a dead man’s switch app detect an accident?
Not necessarily. Ondira identifies a missing check-in and notifies people according to the settings. It does not identify the reason for the absence.
Is it the same as an emergency button?
No. A button lets someone actively ask for help. A check-in requires regular confirmations and reacts when they are missing, after an interval and any further waiting periods.